Patents by Inventor James S. Fritz

James S. Fritz has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • Method of isolating an analyte using a solid phase extraction medium
    Patent number: 5618438
    Abstract: A functionalized macroporous poly(styrene divinylbenzene) particle comprises at least one ionic functional group covalently bonded thereto, the functionalized particle having sorptive capability towards an analyte, said functional group being present in the range of 0.1 to 2.5 milliequivalents per gram of poly(styrene divinylbenzene). The functionalized particles can be used in a packed column or enmeshed in a nonwoven web for utility in solid phase extraction applications.
    Type: Grant
    Filed: May 23, 1995
    Date of Patent: April 8, 1997
    Assignee: Minnesota Mining and Manufacturing Company
    Inventors: James S. Fritz, Philip J. Dumont, Donald F. Hagen, Craig G. Markell, Luther W. Schmidt
  • Self-wettable solid phase extraction medium
    Patent number: 5616407
    Abstract: A functionalized macroporous poly(styrene divinylbenzene) particle comprises at least one ionic functional group covalently bonded thereto, the functionalized particle having sorptive capability towards an analyte, said functional group being present in the range of 0.1 to 2.5 milliequivalents per gram of poly(styrene divinylbenzene). The functionalized particles can be used in a packed column or enmeshed in a nonwoven web for utility in solid phase extraction applications.
    Type: Grant
    Filed: May 30, 1995
    Date of Patent: April 1, 1997
    Assignee: Minnesota Mining and Manufacturing Company
    Inventors: James S. Fritz, Donald F. Hagen, Craig G. Markell
  • Modified resins for solid-phase extraction
    Patent number: 5230806
    Abstract: A process of treating aqueous solutions to remove organic solute contaminants by contacting an aqueous solution containing polar organic solute contaminants with a functionalized polystyrene-divinyl benzene adsorbent resin, with the functionalization of said resin being accomplished by organic hydrophilic groups such as hydroxymethyl, acetyl and cyanomethyl.
    Type: Grant
    Filed: December 5, 1991
    Date of Patent: July 27, 1993
    Assignee: Iowa State University Research Foundation, Inc.
    Inventors: James S. Fritz, Jeffrey J. Sun
  • Modified resins for solid-phase extraction
    Patent number: 5071565
    Abstract: A process of treating aqueous solutions to remove organic solute contaminants by contacting an aqueous solution containing polar organic solute contaminants with a functionalized polystyrene-divinyl benzene adsorbent resin, with the functionalization of said resin being accomplished by organic hydrophilic groups such as hydroxymethyl, acetyl and cyanomethyl.
    Type: Grant
    Filed: February 4, 1991
    Date of Patent: December 10, 1991
    Assignee: Iowa State University Research Foundation, Inc.
    Inventors: James S. Fritz, Jeffrey J. Sun
  • Liquid chromatographic determination of water
    Patent number: 4970170
    Abstract: A sensitive method for the determination of water in the presence of common interferences is presented. The detection system is based on the effect of water on the equilibrium which results from the reaction aryl aldehydes, such as cinnamaldehyde and methanol in the eluent to form cinnamaldehyde dimethylacetal, plus water. This equilibrium is shifted in a catalytic atmosphere of a hydrogen ion form past column reactor. The extent of the shift and the resulting change in absorbance are proportional to the amount of water present.
    Type: Grant
    Filed: July 18, 1988
    Date of Patent: November 13, 1990
    Assignee: Iowa State University Research Foundation, Inc.
    Inventors: Nancy E. Fortier, James S. Fritz
  • Decontamination of water using nitrate selective ion exchange resin
    Patent number: 4944878
    Abstract: A method for nitrate decontamination of water which involves passing the water through a bed of alkyl phosphonium anion exchange resin which has pendant alkyl groups of C.sub.3 or larger.
    Type: Grant
    Filed: November 16, 1989
    Date of Patent: July 31, 1990
    Assignee: Iowa State University Research Foundation, Inc.
    Inventors: James E. Lockridge, James S. Fritz
  • Method and apparatus for chromatographic quantitative analysis
    Patent number: 4272246
    Abstract: An improved apparatus and method for the quantitative analysis of a solution containing a plurality of anion species by ion exchange chromatography which utilizes a single eluent and a single ion exchange bed which does not require periodic regeneration. The solution containing the anions is added to an anion exchange resin bed which is a low capacity macroreticular polystyrene-divinylbenzene resin containing quarternary ammonium functional groups, and is eluted therefrom with a dilute solution of a low electrical conductance organic acid salt. As each anion species is eluted from the bed, it is quantitatively sensed by conventional detection means such as a conductivity cell.
    Type: Grant
    Filed: August 20, 1979
    Date of Patent: June 9, 1981
    Assignee: The United States of America as represented by the United States Department of Energy
    Inventors: James S. Fritz, Douglas T. Gjerde, Gabriella Schmuckler